The United States Postal Service Office of Inspector General (OIG) of the United States Postal Service was created by federal statute in 1996, assuming internal oversight duties over the United States Postal Service (previously carried out by the United States Postal Inspection Service, in addition to their federal law enforcement duties). The Inspector General of the United States Postal Service, who is independent of postal management, is appointed by and reports to the Board of Governors of the United States Postal Service. The current Acting Inspector General is Tammy L. Whitcomb.

As one of the federal Offices of the Inspector General, the purpose of the OIG is to prevent, detect, and report fraud, waste, and program abuse, and promote efficiency in the operations of the USPS.